v1.8.7

SpecialFunctions v1.8.7

Diff since v1.8.6

Closed issues:

• More gamma_inc_inv Failures (#390)
• gama_inc_inv fails for valid arguments (#403)
• Can't install this package (#405)

Merged pull requests:

• Fix gamma_inc_inv for some subnormal results (#404) (@devmotion)
• Backport fix in #404 to SpecialFunctions 1.8 (#406) (@devmotion)