Pyarmor

* Fix restrict mode 3 bug: the obfuscated script crashes or complains of this error: `This function could not be called from the plain script` (219)
* Fix bug: the obfuscated script raises unknown opcode error when the script is obfuscated by `obf_code=2` if there is recursive function call
* Fix command `init` and `config` bug: the entry script is set to `.` other than empty when passing `--entry=""`
* Fix bug: the traceback will print very long line if the obfuscated script raises exception
* Fix bug: in some special cases the obfuscated scripts which are obfuscated with`--enable-suffix` still conflict with other obfuscated packages
* Refine the error message as violating restrict mode
* The obfuscated script will raise exception `ReuntimeError` other than quit directly when something is wrong
**Now it will print a pretty traceback to find where is the problem**
* When generating `license.lic` for the obfuscated scripts, the license version information will be embedded into the license file implicitly
* Do not transfer exception type to `PytransformError` as pyarmor initializes failed

**Upgrade notes:**

The license file generated by this version doesn't work with the old obfuscated scripts. There are 2 solutions for this case:

* Still generating the license file with old version pyarmor
* Or obfuscating the scrips again by new version pyarmor

* Fix restrict mode 3 bug: the obfuscated function failed if it's called from generator function even in the obfuscated script.
* In pack command it will try to use the encoding `coding: xxx` in the first comment line of `.spec` file

* Fix pack issue: it will raise `UnicodeDecodeError` when the source path includes non-ascii characters(217)
* Fix obfuscate issue for Python2: it will raise `UnicodeDecodeError` when the source path includes non-ascii characters
* Refine pack command: it will print the output of PyInstaller to the console either

* Refine pack command. Now it's easy to pack the obfuscated scripts with an exists `.spec` file, just specify it by `-s`, refer to https://pyarmor.readthedocs.io/en/latest/advanced.html#bundle-obfuscated-scripts-with-customized-spec-file

* Change the plugin search policy, do not support enviorment variable `PYARMOR_PLUGIN`, but search folder `plugins` in the pyarmor package path.
* Add a new path `plugins` in the package source, there are several common
plugins. So it's easy to check internet time by this way
shell
pyarmor obfuscate --plugin check_ntp_time foo.py

Before that both of these lines should be inserted into `foo.py`
python
{PyArmor Plugins}
PyArmor Plugin: check_ntp_time()

* Fix pack bug: `pyi-makespec: error: unrecognized arguments: -y` if extra options are passed
* Document command `pack` in details: https://pyarmor.readthedocs.io/en/latest/man.html#pack

* Fix pack issue: `pyi-makespec` doesn't work
* Add new platform: `uclibc-armv7`
* Fix issue: guess encoding failed if there are non-ascii characters in the second line
* Document how to work with Nuitka,
https://pyarmor.readthedocs.io/en/latest/advanced.html#work-with-nuitka