Solarpy

Added
- binder example
- logo (svg and png)

Changed
- importing. Added modules to __init__, so "import solarpy" is sufficient

Added
- panel class, that allows to define solar panels as objects. Tests and NB example

Changed
- "B_nth_day" function is now called "B_nday"
- some functions names to all-lowercase
- test file: test_solar_radiation.py → test_radiation.py
- improved coverage in general, docstrings, unused imports...etc

Removed
- the possibility of passing arrays containing datetime objects in some functions
- excessive error handling structures

Added
- changelog file

Changed
- modified how date and time is handled: instead of defining the date and time as a "day_of_the_year" integer (1->365), hour integer (0->23) and minutes (0->59) integer, now proper datetime objects are used. Therefore, i.e.:
sunset_time(n, lat) becomes sunset_time(date, lat)
theta(n, lat, beta, surf_az, hour, minute) becomes theta(date, lat, beta, surf_az)
- "solar_time" function becomes "standard2solar_time" to reflect that the input is a datetime object with standard local time, and the output is the solar local time.
- improved error raising and handling

Added
- First release