MFC r301235:
dhclient(1): correct obvious mismatch in get_char().

Correct switch between current and previous line buffers when
encountering a carriage return in the input.

CID: 1305719
Obtained from: OpenBSD (CVS rev. 1.30)

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

In read_string(), when the last character was a backslash, unincrement
the output index instead of keeping what ever trash was in the buffer.

Reported by: iedowse

MFOpenBSD rev 1.9: fix a buffer overflow when processing config file
lines that are exactly 81 characters in length.

Obtained from: OpenBSD
MFC After: 3 days

Add __FBSDID to all .c files in dhclient to aid in determining file
versions when dealing with user problems.

This commit was generated by cvs2svn to compensate for changes in r147072,
which included commits to RCS files with non-trunk default branches.

Import the OpenBSD dhclient as shipped with OpenBSD-3.7 (the tag
OPENBSD_3_7).