Pdb-tools

After a few months of testing, no major issues have been reported, so bumping the status from RC to Stable.

Release candidate. Most of the issues should be fixed, tools have been tested thoroughly on a number of different scenarios.

Bug fixes and minor updates.

This is a complete re-write of the `pdb-tools` code and does not guarantee backwards compatibility with the previous version.

New

- [pdb_tidy.py](pdb_tidy.py)
Adds TER statements whenever there is a break in residue numbering/chain ids. Adds END statement. (926102993d84991d25b3df869f762f2abb905672)

Modifications

- [pdb_format.py](pdb_format.py)
Add generic line length check for non ATOM/HETATM/TER/END records (2c7e000112c8f6022d977ccc5e2d354563813966, 690f2b5fec76f1938bcdd03a03f040cdc6d6f299)
- [pdb_striphet.py](pdb_striphet.py)
Preserve *all* coordinate section records except HETATM (ae67b6a07d4fcedd3301d9a29b1c188e0d45b355)
- [pdb_linewidth.py](pdb_linewidth.py)
Removed ATOM/HEATM filtering. Now acts on all lines (7b232d34bb9ea2b54a49c5a7b0cb3bb5124f669c)
- [pdb_fetch.py](pdb_fetch.py)
Updated URLs to download PDBs (ba91d75dcccacea376e6f846af98fce18975abca)

Others

- Minor fixes (6842f6de1001dced8efca6ac8953ce5ab1fabe15, b138c6cefc12a0cb766bae079135e896d165a58c, 227d019bcac71db68aec63f42789b60a16ec5472)

This second stable release of the pub-tools includes 26 new commits since the original release in August 2015.