adds base64 decoding (fixes #5656)
improves efficiency, moves alias to deprecated.jl, removes trailing whitespace
Merge remote-tracking branch 'upstream/master' into base64_decode_#5656

Conflicts:
	base/deprecated.jl
update old names in other files
avoid creating new array for each 4 byte block
Merge remote-tracking branch 'upstream/master' into base64_decode_#5656

Conflicts:
	NEWS.md
	base/deprecated.jl
Constify char * arguments in various API functions
Constify windows and Linux specific dynlib funcs
Default values function arguments vs Python

Julia and Python handle default values of function arguments differently. Julia evaluates them every time the function is called and in python they are evaluated only once when the function is defined.
Remove const qualifier from jl_ver_* functions returning int
Merge pull request #9508 from bkamins/patch-1

Default values function arguments vs Python
Merge pull request #9420 from lorrden/master

Constify char * arguments in various API functions
Merge pull request #9512 from waTeim/waT/rqual

Remove const qualifier from jl_ver_* functions returning int
Merge pull request #9157 from amartgon/base64_decode_#5656

adds base64 decoding (fixes #5656)